1<html> 2<head> 3 <title>BOOST_PP_LIST_TRANSFORM</title> 4 <link rel="stylesheet" type="text/css" href="../styles.css"> 5</head> 6<body> 7 <div style="margin-left: 0px;"> 8 The <b>BOOST_PP_LIST_TRANSFORM</b> macro transforms each element in a <i>list</i> according to a supplied transformation. 9 </div> 10 <h4>Usage</h4> 11 <div class="code"> 12 <b>BOOST_PP_LIST_TRANSFORM</b>(<i>op</i>, <i>data</i>, <i>list</i>) 13 </div> 14 <h4>Arguments</h4> 15 <dl> 16 <dt>op</dt> 17 <dd> 18 A ternary predicate of the form <i>op</i>(<i>d</i>, <i>data</i>, <i>elem</i>). 19 This transformation is expanded by <b>BOOST_PP_LIST_TRANSFORM</b> for each element in <i>list</i> with the next available <b>BOOST_PP_WHILE</b> iteration, 20 the auxiliary <i>data</i>, and the current element in <i>list</i>. 21 </dd> 22 <dt>data</dt> 23 <dd> 24 Auxiliary data passed to <i>pred</i>. 25 </dd> 26 <dt>list</dt> 27 <dd> 28 The <i>list</i> to be transformed. 29 </dd> 30 </dl> 31 <h4>Remarks</h4> 32 <div> 33 This macro expands <i>op</i> for each element in <i>list</i>. 34 It builds a new <i>list</i> out of the results of each call. 35 If, for example, <i>list</i> is (<i>a</i>, (<i>b</i>, (<i>c</i>, <b>BOOST_PP_NIL</b>))), 36 this macro expands to... 37 <div> 38 (<i>op</i>(<i>d</i>, <i>data</i>, <i>a</i>), (<i>op</i>(<i>d</i>, <i>data</i>, <i>b</i>), (<i>op</i>(<i>d</i>, <i>data</i>, <i>c</i>), <b>BOOST_PP_NIL</b>))) 39 </div> 40 </div> 41 <div> 42 Previously, this macro could not be used inside <b>BOOST_PP_WHILE</b>. 43 There is no longer any such restriction. 44 It is more efficient, however, to use <b>BOOST_PP_LIST_TRANSFORM_D</b> in such a situation. 45 </div> 46 <h4>See Also</h4> 47 <ul> 48 <li><a href="list_transform_d.html">BOOST_PP_LIST_TRANSFORM_D</a></li> 49 </ul> 50 <h4>Requirements</h4> 51 <div> 52 <b>Header:</b> <a href="../headers/list/transform.html"><boost/preprocessor/list/transform.hpp></a> 53 </div> 54 <h4>Sample Code</h4> 55<div><pre> 56#include <<a href="../headers/arithmetic/dec.html">boost/preprocessor/arithmetic/dec.hpp</a>> 57#include <<a href="../headers/list/transform.html">boost/preprocessor/list/transform.hpp</a>> 58 59#define LIST (1, (3, (2, (5, <a href="nil.html">BOOST_PP_NIL</a>)))) 60 61#define OP(d, data, elem) <a href="dec.html">BOOST_PP_DEC</a>(elem) 62 63<a href="list_transform.html">BOOST_PP_LIST_TRANSFORM</a>(OP, 3, LIST) 64 // expands to (0, (2, (1, (4, <a href="nil.html">BOOST_PP_NIL</a>)))) 65</pre></div> 66 <hr size="1"> 67 <div style="margin-left: 0px;"> 68 <i>� Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i> 69 </br><i>� Copyright Paul Mensonides 2002</i> 70 </div> 71 <div style="margin-left: 0px;"> 72 <p><small>Distributed under the Boost Software License, Version 1.0. (See 73 accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or 74 copy at <a href= 75 "http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p> 76 </div> 77</body> 78</html> 79